So I created this app a few years back and have returned to take a look at it and I see that you have implemented this new user onboarding stuff in order to access the app.
I am testing on localhost and have added myself on my developer dashboard, but when I'm redirected back to my client after logging in, I just get a 403 response with no further info.
I assume it has to do with this new user onboarding stiff, but I don't know why it is refusing my user.
I've read the other posts mentioning similar issues but have not found a resolution.
Any advice would be greatly appreciated.